Depends what you mean by "unskilled labour". Literally no skills? Yeah that doesn't exist, and is impossible to exist as even the most simple of motor tasks like walking are learned and therefore "skills".
If by "unskilled labour" you mean jobs that require no formal training and your average person could be trained up well enough to not need to be constantly trained/supervised in a week or two? Then there's lots of those. Maybe "low skilled labour" is slightly better but still a bit misleading (you still develop skills and improve in those jobs, it's just you're "good enough" at it in a relatively short period of time).
Because capitalism, when you're easily replaceable it means the employer can shop around more and find people willing you did the job for less so the pay is low. You aren't paid by how hard you work, but by the "value" you bring and how hard it is to find someone else.